Reviews & Analysis

Heat-producing elements like uranium and thorium are depleted in the lower crust. The geochemistry of crustal rocks suggests ultrahigh melting temperatures are needed to produce this depletion and may also help stabilize the crust.

Our oceans are changing rapidly, with climate-driven shifts in circulation and nutrient cycles reshaping marine ecosystems in profound ways. One of the most visible and disruptive outcomes is the explosive growth of Sargassum — a floating brown alga that has, since 2011, formed vast rafts stretching thousands of kilometres across the Atlantic Ocean.

The oxygenation of Earth’s atmosphere ~2.45–2.30 billion years ago may have initiated in the oxidized bottom waters of marine shelves, according to a synthesis of thallium and nitrogen isotopes and cyanobacteria phylogenetic records.

Complex numerical simulations show how slivers of continental crust in the ocean were shaved from continental margins and then transported by transform fault complexes.

High-resolution global climate simulations reveal that mesoscale moisture convergence, rather than thermodynamic effects alone, drives much of the projected intensification of extreme rainfall under warming. These results demonstrate that better representing mesoscale dynamics substantially improves the robustness of future rainfall projections, offering critical insights for flood-risk assessment and climate adaptation.

Our simulations identified how small, swirling ocean eddies carry and mix warm water beneath Thwaites ice cavities in the Amundsen Sea Embayment, West Antarctica. Much like how storms in the atmosphere batter coastlines, these energetic eddies enhanced mixing at the ice-shelf base and substantially increased submarine melting.

Drill cores from the mid-ocean ridge in the South Atlantic suggest that mass-wasting deposits formed against ridge faults host abundant calcite and so may store substantial amounts of carbon dioxide.

Nitrite, a key player in the ocean’s nitrogen cycle, accumulates in deoxygenated waters for reasons that remain unclear. Our chemostat and three-dimensional models showed that competition amongst aerobic (oxygen-dependent) and anaerobic (oxygen-independent) microbes, rather than a lack of nitrite consumers, contributes to nitrite’s accumulation in anoxic waters.

Geochemical heterogeneity in near-continent oceanic volcanism hints at overlooked mantle enrichment processes. Models and data from the Indian Ocean suggest that rift-related convective instabilities can disturb the ancient roots of continents. This process sweeps geochemically enriched domains into the oceanic asthenosphere over tens of millions of years, explaining the observed longevity of geochemical mantle anomalies.

The building blocks that formed the Earth remain enigmatic. The potassium isotopic composition of some ancient and modern rocks suggests the composition of the early Earth was modified by the Moon-forming impact, but that traces of its original composition survived mixing and are sampled by some extant mantle plumes.

Our analysis of mineral deposits in a cave in North Greenland reveals a sensitive High Arctic Late Miocene climate at moderate CO₂ levels, balanced between wetter and warmer permafrost-free conditions and ephemeral glacier expansion.

Analysis of satellite remote sensing and geophysical data reveals that following the loss of stabilizing fast ice, an Antarctic Peninsula glacier retreated at a record pace due to a fast calving and flotation process that occurred as it reached an ‘ice plain’, where the ice is lightly resting on bedrock.

A negative sulfur isotope excursion occurred across Eurasia during the last deglaciation. An analysis suggests thawing permafrost might be responsible.

Accounting for the rheology of Earth’s mantle calls for a re-evaluation of the seismic and tsunami hazard posed by subduction zones, especially in the Lesser Antilles.

Over a prolonged period of hydrologic drought, the major ion chemistry of a North American river dramatically shifted, revealing reduced lateral carbon transport due to secondary carbonate formation. These observations expose a natural limit to the inorganic carbon carrying capacity of rivers.

High-resolution satellite maps of the contiguous USA spanning 35 years reveal a fundamental shift in land disturbances: the area affected by human-directed disturbances is decreasing, whereas land damaged by ‘wild’ disturbances (like fire, vegetation stress, wind, and geohazards) is surging. This work also uncovers evolving patterns in the frequency, size, and severity of disturbances.

Geophysical observations and computer simulations suggest that a tectonic plate segment is delaminating in the area that generated a large earthquake that destroyed Lisbon in 1755. This rare oceanic delamination might be a precursor of subduction initiation, which could explain the cause of several large earthquakes in the Atlantic Ocean.

A review of observation-based evidence suggests that four interconnected Earth system tipping elements have moved towards their critical thresholds, highlighting the need for better monitoring and increased mitigation efforts.

A dataset of cosmogenic beryllium-7 measurements is compiled and used to quantify aerosol deposition rates over the global ocean. The findings suggest that aerosol deposition onto oceans has been underestimated in a widely used atmospheric composition model, GEOS-Chem, resulting in an overestimation of aerosol lifetime over oceans.